DD-WRT is a nice third-party firmware interface for a host of cheap wireless routers, most prominently Broadcom based routers like Linksys WRT54G.
It has a nice web based administration interface, but this interface is not rendered properly in WebPositive build hrev488 on Haiku r1alpha2.

Provided is screenshot with BeZillaBrowser used as reference since it renders the interface properly and also handles the JavaScript used on the page.

But from the screenshot, I don't see what the big problem is. Some frames are missing, but the interface looks functional. For all I know, it could be a problem in the page and not WebPositive. Also, could you explain what is non-functional about the Javascript? How about other WebKit browsers, do they all render this interface "correctly"?

The interface renders properly from a visual standpoint, but something's still wrong as far as actually handling it goes. Clicking any of its tabs to go to the corresponding configuration subsection triggers the appropriate http digest authentication dialog, but after one enters credentials, Web+ simply sits there waiting, seemingly for a response, until finally failing with a network read error several minutes later.

Seems there's still an issue with this one: while browsing through the interface generally works, attempting to apply/save settings winds up hitting the interface's apply.cgi and then stopping dead without actually executing it properly. Tested with hrev47561 and DD-WRT v24.

Doesn't appear to have made a difference, unfortunately. Web+ does indicate that the apply.cgi request finished both before and after that change, but simply stops there. Is there any network traffic tracing that could be enabled or whatnot, that might yield a better picture of what's going on?